1. Field of the Invention
The present invention relates generally to a method and an apparatus for selecting a cell in a mobile communication network, and more particularly, to a method of selecting a cell in order to access a network or update a position.
2. Description of the Prior Art
In current module communication systems, 2nd generation systems and 3rd generation systems are mainly used, and Long Term Evolution (LTE), which corresponds to a 4th generation system, is currently being standardized.
Basically, an LTE system supports only a service in a Packet Switched (PS) scheme. Accordingly, in order to provide a voice call to a user, the LTE standard proposes a Circuit Switch (CS) FallBack (FB) service.
FIG. 1 illustrates a conventional CSFB service. As illustrated in FIG. 1, when a voice call is generated for a terminal camping in an LTE system, the CSFB service refers to a service of handing over the mobile terminal to a conventional 2G/3G legacy system to connect the voice call.
While some LTE cells support a CSFB function, some LTE cells do not support the CSFB function, depending on a service provider network situation.
When an LTE terminal is located within an LTE cell that does not support the CSFB, if the LTE terminal is a single radio LTE terminal, then the terminal may use only the 2G/3G legacy system, without using LTE at all, but if the LTE terminal is a dual radio LTE terminal, the terminal may receive a PS service using LTE and a voice service using 2G/3G.
When the single radio LTE terminal uses only the legacy system, without using LTE, in the cell, which does not support the CSFB service, and then moves to the cell that supports the CSFB service, the signal radio LTE terminal may not use LTE.